Linux foundation - threads

1. Thread concept 1.1 comparison between threads and processes Threads are similar to processes, both of which have PCB s The underlying functions of both are the same, and both use clone Processes can become threads Under Linux, thread is the smallest unit of execution; process is the smallest uni ...

Added by pcwizzzz on Thu, 18 Jun 2020 08:51:58 +0300

Five communication modes between processes

Source: https://blog.csdn.net/wh_sjc/article/details/70283843   IPC (InterProcess Communication) refers to the communication or exchange of information between different processes. IPC usually includes pipeline (including nameless pipeline and named pipeline), message queue, semaphore, shared storage, socket, Streams, etc. Soc ...

Added by ValdouaD on Mon, 18 May 2020 09:00:24 +0300

MySQL database functions

1, Date and time functions 1. Function to get the current dateIt's the same. It's different CURDATE() : Used to get the current date of the system CURRENT_DATE() Used by the system to get the current date mysql> select CURDATE(),CURRENT_DATE(); 2. Get function of current time CURTIME() : Used to get the current time of the system mysql& ...

Added by brighton on Thu, 14 May 2020 12:11:49 +0300

fork function and vfork function

fork function In many applications, creating multiple processes is an effective method for task decomposition. For example, a network server process can create a new subprocess to process each request while listening for client requests. At the same time, the server process will continue to listen for more client connection requests. Decomposin ...

Added by vinny69 on Wed, 13 May 2020 07:56:54 +0300

centos 6.8 installation of Redis and simple use

1, Install dependency package and prepare environment. yum install -y gcc Depending on the package, you can install it according to the prompts at compile time. But gcc must be installed. 2, 1. Download the tar package, install and start it. wget http://source.goyun.org:8000/source/Redis/redis-3.2.9.tar.gz --2018- ...

Added by lnfreish on Wed, 06 May 2020 03:49:40 +0300

Use of log4j

1. Simple use Only one jar package of log4j needs to be imported, and the log4j.properties configuration file under the src directory will be loaded by default 1. Print log to console log4j.properties configuration file content #Set the log level to info and output to the console log4j.rootLogger=info,console log4j.appender.console = org ...

Added by jay_bo on Mon, 20 Apr 2020 18:53:38 +0300

[network programming 01] basic knowledge of socket - simple network communication program

1. What is socket Socket is simply a combination of IP address and port, which can communicate with the application of remote host. A host can be determined by IP address, and an application can be determined by port. IP + port can completely determine an application of a host. Socket originated from UNIX, similar to a special file, can be open ...

Added by munuindra on Wed, 15 Apr 2020 11:46:48 +0300

Summary of problems encountered in docker environment required for k8s deployment

Alibaba cloud's one click deployment script is used for deployment: curl -fsSL https://get.docker.com | bash -s docker --mirror Aliyun Create the required directory: mkdir -p /etc/docker /data/docker Then modify the configuration file of docker: /etc/docker/daemon.json {   "graph": "/data/docker",   "storage-driver": "overlay2",   "insecure-re ...

Added by zenag on Mon, 23 Mar 2020 11:23:01 +0200

Difference between TCP and UDP

TCP In order to facilitate the development of network applications, Berkeley University in the United States implements a kind of communication protocol Socket on Unix, which enables programmers to access TCP/IP conveniently; Use Socket of TCP/IP to communicate: The server program binds a socket ...

Added by boogybren on Fri, 06 Mar 2020 07:30:09 +0200

linux file system related commands (df/du/fsck/dumpe2fs)

1, File system view command df format df [options] [mount point] option Name Effect -a Display all file system information, including special file systems, such as / proc,/sysfs -h Display capacity in customary units, such as KB,MB or GB -T Show file system types -m Display capacity in MB -k Display capacity in kilobytes. The def ...

Added by seventheyejosh on Fri, 28 Feb 2020 09:52:15 +0200